Method of making an oral cleanser



ct. 15, 19 MURRAY 3,405,437

METHOD OF MAKING AN ORAL CLEANSER Original Filed NOV. 10, 1964 INVENTORMYLES N. MURRAY BY azmhm 6.0

ATTORNEYS United States Patent METHOD OF MAKING AN ORAL CLEANSER MylesN. Murray, Chagrin Falls, Ohio, assignor to Industrial Electronic RubberCompany, Twinburg, Ohio Original application Nov. 10, 1964, Ser. No.410,075, now

Patent No. 3,242,519, dated Mar. 29, 1966. Divided and this applicationSept. 17, 1965, Ser. No. 488,016

Claims. (Cl. 29450) ABSTRACT OF THE DISCLOSURE Molding a rubber holderhaving a handle part and a curved support extension of general H-shapein crosssection, with the ends of the web of the latter outwardlyconverging. Cutting a slitted resilient body of general trapezoidalshape by placing one pad of sponge material on another, compressing thepads, and forcing an outer shaping blade and a slitting blade normallythrough the compressed pads, so that the body blanks when released andthe slits as well assume the trapezoidal form. Applying a resilient bodyto the holder by stretching its slit portion over the outer wall of thesupport extension and about the Web of the same.

This is a division of application Ser. No. 410,075, filed Nov. 10, 1964,now Patent No. 3,242,519.

This invention relates to an improved method of making an oral hygienedevice intended principally to be applied for cleaning human teeth andalso to the manner in which the device is made.

Such device is generally referred to as an oral cleanser, although ithas some further utility as hereinafter noted, and it is of the type inwhich a sponge body or an assembly of strips of sponge material isprovided for insertion in the mouth and chewing to effect scrubbing ofthe teeth. The active sponge part or parts are preferably arranged andsupported along an arc conforming loosely to half of the dental arch,with enough working surfaces simultaneously to engage the upper andlower teeth of the half arch fully about the same. A handle is of courseprovided for inserting and removing the device and, with the approximatesize and shape indicated, both sides of the mouth can be cleaned withonly two insertions, the device being turned over in being moved fromone side to the other.

The known forms for such an oral cleanser have utilized sponge rubber invariously shaped bodies affixed by cementing or the like to a suitablesupport from which the handle projects. It has developed that suchdevices are not particularly inexpensive, as compared for example toother more conventional toothbrushes and the like, and the chewingaction which produces the desired scrubbing of the teeth does of coursein time break down the sponge and necessitate disposal of the entireproduct. No practical proposal is known to have been made which wouldprovide readily separable support and active components in an assemblypermitting the latter, this being the sponge mass which is subject tothe attrition, to be removed and replaced with a new component inassociation with the same support. It is therefore a primary object ofthe present invention to provide an oral hygiene device of this class,in which this last noted composite character and mode of utilization arerealized.

It is also an object of the invention to provide a method of making anew form of assembly [for such an oral cleanser in which a single bodyof the active material provides, in association with a separable holder,surfaces for substantially full engagement simultaneously with allexposed surfaces of both the upper and lower teeth about approximatelyhalf of the dental arch.

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Another important object of the invention is to provide an extremelyfacile and practical method of manufacture of sponge bodies to be usedas the active components in oral devices of the class discussed.

Other objects and advantages of the present invention will becomeapparent as the following description proceeds.

To the accomplishment of the foregoing and related ends the invention,then, comprises the features hereinafter fully described andparticularly pointed out in the claims, the following description andthe annexed drawings setting forth in detail certain illustrativeembodiments of the invention, these being indicative, however, of but afew of the various ways in which the principle of the invention may beemployed.

In said annexed drawings:

FIG. 1 is a perspective view of a new oral hygiene device in accordancewith the present invention;

FIG. 2 is a further perspective view, on a slightly enlarged scale, ofthe holder component of the device;

FIG. 3 is a view of a cutter assembly used in the manufacture of thesponge or active body of the oral device, with this assembly being shownon edge and thus viewed in this figure from the bottom;

FIG. 4 is a cross-sectional view of the noted cutter assembly in workingopposition to a representative support on which two pads of spongerubber are placed in superimposed relation for cutting to produce theparticular body needed for the oral hygiene device;

FIG. 5 is a view of the same assembly in FIG. 4, but showing thecondition in which the cutting device has bean forced to penetrateapproximately the top sponge P FIG. 6 is a similar view in which thecutting assembly has been fully forced through both of the sponge pads,this being the terminal condition in the cutting operation beforeretraction of the cutting assembly; and

FIG. 7 is a side elevation of the section produced by the stepsillustrated in FIGS. 4-6, this section comprising two bodiesrespectively cut from the sponge pads.

Referring now to the drawings in detail, the device shown in FIG. Ibasically comprises a holder 10 and an active body section 11 detachablyassociated with such holder. The holder 10 is shown separately in FIG. 2and will be seen therefrom to comprise, as parts of a single piecepreferably made by rubber molding, a fairly heavy generally triangularhandle 12 and an integral arcuate extension 13 which is of generalH-shape in radial cross-section.

The support extension 13 thus is formed with a curved vertical outerwall 14, with the handle 12 projecting angularly from one end of thiswall as illustrated in a plane substantially normal to the axis of thecurvature of the wall 14. At the inner surface of the wall 14,approximately along the longitudinal center thereof, there is aninwardly projecting horizontal web 15 having tapered ends as shown toprovidea reduction of the arcuate length as compared to the outer wall14. The support extension 13 is completed by a vertical inner wall 16integral with the reduced end length of the web portion 15 andprojecting equally above and below the latter. This inner wall 16 isonly slightly longer than the edge of the web portion at which it isjoined to the same, and thus of noticeably smaller extent than the outerwall 14. The vertical inner and outer walls are approximately concentricand the end wall 16 has its ends noticeably rounded, so that theprojection thereof in a plane would be elliptical, for a purpose to belater explained.

A comparison of FIGS. 1 and 2 will clearly show that the active bodycomponent 11 of the device is formed as a second single piece in suchmanner as to be fitted over the support extension 13 and sufiicientlyfixed in place for the chewing action earlier discussed, While beingremovable for disposal and replacement with another body of similarformation. This active component 11 preferably will be spongy and made,for example, from a high purity sponge rubber such as silicone sponge.With further regard to materials, the holder can be readily molded ofsilicone rubber in the proportions shown, with the degree of resiliencedesired for its indicated support and handling functions.

When assembled with the holder 10, the sponge 11 is generallytrapezoidal in longitudinal section, The sponge is provided with acenter slit, between its outer faces, permitting this body to bestretched over the inner wall 16, the elliptical shape of the latterfacilitating such operation, and thus disposed to extend fully about theweb 15 between the side walls 14 and 16. On each of its exposed longsides, that is, at the top and bottom of the assembled device, thesponge body is provided with a lengthwise extending groove, such asappears at 17 in FIG. 1. It will be obvious that these body groovesaccommodate respectively the upper and lower teeth of the user of thedevice in resilient resisting penetration, with all teeth engaged at allexposed surfaces of the same over the half dental arch.

The dimensions of the sponge body 11 relative to the holder 10 are ofcourse such that the former can be sufficiently stretched outwardly ofits center slit for passage over the inner wall 16 of the holder. Thethus accomplished engagement about the web 15 will maintain sufiicienttension in the body to hold the same firmly in place, while stillpermitting the ready removal thereof when it is desired to discard theparticular sponge because of wear or any other reason.

With regard now to the method of making the sponge body for such oralcleansers, the steps are illustrated in the remaining figures in whichthe apparatus is more or less schematically shownvas needed forproducing a single body. Actually, as will appear, this illustrativeoperation produces two separate bodies, and the distinction being madehere is that between a single operating sequence and multiplication byincreasing the number of cutters operable in the same head structure andthe like. The individual cutter used comprises a mounting board 18having a first continuous blade 19 projecting downwardly from one sideof the board in the general shape of a rectangle with rounded ends.Within this continuous outer blade 19, there is a centered straightblade 20 which is approximately the same length as the straight sides ofthe blade 19. Both blades have lower or outer knife edges and projectapproximately the same distance from the same side of the cutting board18.

Two pads 21 and 22 of the sponge material to be used, such as theaforenoted silicone sponge, are placed on a relatively fixed support,such as the representative table 23, with one resting on the other inregister. The mounting board 18 of the cutter assembly is brought inparallel opposition to the support 23 above the top pad 21, with itsblades of course projecting downwardly, and force is applied to the topof the cutting board suflicient to drive the blades fully through thetwo pads.

The projection of the blades 19 and 20 is less than the normaluncompressed total thickness of the two sponge pads 21 and 22, and thelatter are not peripherally restrained. The result of these conditionsis that the pads are substantially compressed in the cutting operationas shown in the progression apparent in FIGS. 4, 5 and 6. It will thusbe appreciated that the blades cut through the sponge pads or layerswhile the latter are undergoing deformation, so that the actual lines ofcutting are not normal to the planes of the pads upon release by fullwithdrawal of the cutter assembly.

In FIG. 7, there is illustrated the slug cut by the foregoing operationand it will be seen that this actually provides two mirror image spongebodies 24 and 25 which,

while still superimposed, have definitely convex ends and the smallestlength occurring at the interface 26. Moreover, the slit cut by thecenter blade 20 will also be tapered from each of the top and bottomfaces inwardly toward this parting or separation line 26, the ends ofthe slit in the body 24 being indicated by the dashed lines 27 and thoseof the slit in the body 25 by the dashed lines 28. Accordingly, simplyseparating this slug of FIG. 7 provides two sponge bodies each havingboth the desired generally trapezoidal longitudinal section and atapered center slit which roughly corresponds to the outer taper.

The sponge bodies thus produced, in the form shown by the bodies 24 and25, have fairly sharp outer edges, and it is preferred that these beremoved, for example, by tumbling or any suitable abrading expedient inorder to provide the rounding of the edges apparent in the finishedproduct shown in FIG. 1. Each of the sponge bodies thus produced is alsogrooved to provide the side face center slots 17 as earlier discussed,with this operation capable of being performed by a simple power saw.

It will be appreciated that the method described above requires only thesimplest of apparatus and uniquely relies upon cutting the body blankswhile the pads from which they are out are deformed. The pads cantherefore be of standard stock and cutters in the usual and preferrednormal relation to the work can be utilized. Moreover, two bodies areproduced by each cutter in this operation and the only further work tobe done is the equally easy side grooving and abrasion of sharp edges.In FIGS. 5 and 6, the dashed lines 29 and 30, respectively, areprojections of the initial undistorted cutting plane and show, togetherof course with the curvature of the ends of the sponge pads, the extentto which the cutting stroke which would obtain in a normal operationwithout compression is distorted. In production apparatus, the head willbe provided with a plurality of cutters similar to the one described andlarge pads will be used, in order to produce a multiplicity of thepaired sponge bodies in each cycle.

It will now be obvious that the present improvements concernparticularly the two-part nature of the new oral hygiene device, theform of the sponge, and the preferred method of producing the latter.The manner of use of the device has already been discussed, and anymaterial of requisite purity and resilient character on the order setforth can be employed, whether rubber, plastic or the like. The spongeis significant not only in the resiliency utilized for the scrubbing ofthe teeth, but also as a labyrinthine or cellular body to produce ahydraulic flushing action to reach inaccessible regions in the mouth inthe use of the device, a dentifrice normally being used for thecleansing and being dischargeable from the cells of the sponge to flowover the teeth and gums of the user.

The device can also be used for applying medication, for example, fortreatment of mouth diseases, and the sponge bodies can be originallyfurnished either with or without the particular additive alreadyincorporated. The holder can be made of a material other than rubber,for example, a suitable synthetic resin, with its significant featuresin respect of choice of material being primarily related to stiffness,ease of fabrication, and ability to support the sponge in the intendeduse of the device.

Other modes of applying the principle of the invention may be employed,change being made as regards the details described, provided thefeatures stated in any of the following claims or the equivalent of suchbe employed.

I, therefore, particularly point out and distinctly claim as myinvention:

1. The method of making a disposable sponge for an oral hygiene deviceof the character described, which comprises the steps of placing twopads of sponge stock on a support with one on the other, relativelyadvancing a cutter assembly on the two thus supported pads, with thecutter assembly providing a continuous outer cutting shape in thedirection of the advance and an inner slitting shape, driving suchcutter assembly through the pads while compressing the latter to distortthe normal lines of cutting, the distortion being such as to producefrom the pads two sponge bodies which have normally tapered ends whenreleased from such compression and generally corresponding tapered slitsbetween their respective faces of unequal length.

2. The method set forth in claim 1, in which the two sponge bodies aresubsequently separated for independent use and subjected to an abradingaction to round original sharp edges of the same.

3. The method of making an oral hygiene device, which comprises thesteps of forming a holder having a handle part and a support extensionwhich is of general H-shape in cross-section, said extension therebyhaving a web and adjoining inner and outer walls projecting to bothsides of the same, with the ends of such web being tapered respectivelyinwardly from the inner to the outer wall, cutting from a pad of spongematerial a resilient body corresponding in shape to said supportextension and providing a generally centered slit in the body havingends which are tapered correspondingly as the ends of the Web of thesupport extension, and applying the resilient body to the holderexension by stretching the slit portion of the former over the outerWall of the latter and about the web between the inner and outer walls.

4. The method of claim 3, including producing two resilient bodies at:the same time by supporting two pads of the sponge material with oneplaced on the other, compressing the pads and cutting through both whilecompressed in an action normal to their surfaces to sever the bodiesfrom the pads, with the cut bodies released and assuming normalgenerally trapezoidal shapes.

5. The method of claim 4, including cutting the slits in the two bodiesin the severing of the same from the compressed pads, the ends of theslits thereby becoming tapered when the bodies assume their normalshapes.

References Cited UNITED STATES PATENTS 1,631,133 6/1927 Jones 152441,962,875 6/ 1934 Reber. 2,111,238 3/1938 Doyle 15188 2,251,135 7/ 1941Ikn-ayan et al 83-19 2,323,568 6/ 1943 Rogers 15-244 2,375,518 5/1945Bolle 8319 2,491,274 12/ 1949 McNeill 15-244 XR 2,915,768 12/ 1959 Hall15244 3,105,263 10/ 1963 Ginter 15--244 FOREIGN PATENTS 291,675 6/ 1928Great Britain. 723,815 1/ 1932 France.

CHARLIE T. MOON, Primary Examiner.

